CHANGE OF CHALAATI GLACIER (GEORGIAN CAUCASUS) SINCE THE LITTLE ICE AGE BASED ON DENDROCHRONOLOGICAL AND BERYLLIUM-10 DATA

Autor: Tielidze, L.G., Solomina, O.N, Braucher, Regis, Jomelli, V., Dolgova, E.A., Bushueva, I.S., Mikhalenko, V.N., Brauche, R., Team, A.S.T.E.R.
Přispěvatelé: Ivane Javakhishvili Tbilisi State University (TSU), Victoria University of Wellington, Higher School of Economics [Perm] (HSE), National research university (MAI), Institute of Geophysical Survey of Russian Academy of Sciences, Far Eastern Branch of the Russian Academy of Sciences (FEB RAS), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire de géographie physique : Environnements Quaternaires et Actuels (LGP), Université Paris 1 Panthéon-Sorbonne (UP1)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)
Jazyk: angličtina
Rok vydání: 2020
Předmět:
Zdroj: Ice and Snow
Ice and Snow, 2020, 60 (3), pp.453-470. ⟨10.31857/S2076673420030052⟩
Lëd i Sneg, Vol 60, Iss 3, Pp 453-470 (2020)
ISSN: 2076-6734
DOI: 10.31857/S2076673420030052⟩
Popis: International audience; Glacier variations over the past centuries are still poorly documented on the southern slope of the Greater Caucasus. In this paper, the change of Chalaati Glacier in the Georgian Caucasus from its maximum extent during the Little Ice Age has been studied. For the first time in the history of glaciological studies of the Georgian Caucasus, 10Be in situ Cosmic Ray Exposure (CRE) dating was applied. The age of moraines was determined by tree-ring analysis. Lichenometry was also used as a supplementary tool to determine the relative ages of glacial landforms. In addition, the large-scale topographical maps (1887, 1960) were used along with the satellite imagery - Corona, Landsat 5 TM, and Sentinel 2B. Repeated photographs were used to identify the glacier extent in the late XIX and early XX centuries. 10Be CRE ages from the oldest lateral moraine of the Chalaati Glacier suggest that the onset of the Little Ice Age occurred ~0.73±0.04 kyr ago (CE ~1250-1330), while the dendrochronology and lichenometry measurements show that the Chalaati Glacier reached its secondary maximum extent again about CE ~1810. From that time through 2018 the glacier area decreased from 14.9±1.5 km2 to 9.9±0.5 km2 (33.8±7.4% or ~0.16% yr-1), while its length retreated by ~2280 m. The retreat rate was uneven: it peaked between 1940 and 1971 (~22.9 m yr-1), while the rate was slowest in 1910-1930 (~4.0 m yr-1). The terminus elevation rose from ~1620 m to ~1980 m above sea level in ~1810-2018.; Для реконструкции колебаний ледника Чалаати в Грузии использовались космические снимки, старые карты, повторные фотографии, дендрохронология, лихенометрия и анализ космогенных изотопов. Максимальное наступание ледника в начале малого ледникового периода произошло в ~1250-1330 гг., второй максимум, когда ледник достиг почти такой же длины, датируется примерно 1810 г. С этого времени до 2018 г. площадь ледника уменьшилась с 14,9±1,5 до 9,9±0,5 км2 (33,8±7,4%, или ~0,16% год-1), а его длина сократилась на ~2280 м.
Databáze: OpenAIRE